Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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WASTEWATER TREATMENT APPARATUS AND SYSTEM FOR
OIL AND GAS PRODUCTION WELLS
CROSS-REFERENCE TO RELATED APPLICATIONS
Priority is claimed from provisional patent application U.S. Serial No.
61/961,462
filed on October 15, 2013 and incorporated by reference herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
In general, the present invention relates to an apparatus, system and method
of
evaporating and or treating wastewater associated with well operations. More
particularly,
the present invention provides a closed loop system for the removal of
contaminants from
wastewater while evaporating the water by utilizing a continuously running
evaporator in
communication with a separation tank wherein water is returned to the
evaporator and solids
are left in the separation tank for disposal.
2. Description of the Prior Art
In the oil and gas industry, a major concern facing the field is the ever
growing and
constant concern with environmental impact of oil and gas production coupled
with the ever-
increasing need to maximize efficiency and recovery. Prior art methods that
were perfectly
acceptable just years ago are now politically and environmentally unfriendly
as well as
wasteful in hindsight. Whereas, it was acceptable to allow by products from
well production
to be released into the environment, it is not considered a viable economic or
environmentally
sound method to date.
It is known to treat the wastewater for general reuse and return to the
environment
although the amount of wastewater to be treated and cost of treating can be
prohibitive. It is
also known to evaporate the wastewater or large percentage of such thereby
reducing the
amount of water left to be treated and or returned to the environment.
Evaporation is often
preferred because of its generally light footprint on the environment when
emissions are
controlled and the operation cost of the massive evaporation is not
prohibitive.
Submerged combustion heating is generally a method whereby hot products of
combustion are forced through a liquid or liquid-solid mixture to heat the
liquid or liquid-
solid mixture. An advantage of this heating system is that the heat exchange
occurs directly
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between the hot gaseous products of combustion and the liquid. In a submerged
combustion
system, the hot combustion is typically fuelled by a combination of air and
natural gas.
Another benefit of such application is the natural gas needed to fuel the
evaporation may
come from the well operation thereby eliminating the need for transporting a
fuel.
The operational benefits of evaporation are reduced handling of produced
water,
which streamlines the entire operation; fewer trucks needed to move the
wastewater mean
less site damage, maintenance and general reduced liability; and overall less
dependence on
water haulers eliminates scheduling delays and fees. The environmental
benefits include less
CO2 emissions as the need for trucks is reduced and or eliminated as well as
less road
damage and noise associated with fewer trucks. Other benefits may be reduced
flaring,
improved public perception of evaporation versus injection, and less
likelihood of spills or
surface water contamination.
Large-scale evaporation of significant amounts of wastewater does create
challenges.
In a desalination process, salts, minerals and other various dissolved and
suspended solids are
separated from the water. In a thermal process, as the influent water is
heated, the dissolved
solids become concentrated, increase in weight, and turn into suspended
solids. After the
dissolved solids become suspended, the concentrated solids fall to the bottom
of the tank in
which the heat treating occurs, while the free water moves towards the top of
the tank in the
form of a vapor. The vapor then exits the tank through an opening, most
commonly referred
to as a stack or an exhaust. To continue the desalination process, the solids
eventually must
be removed from the treating tank.
In the prior art, as with a submerged combustion system, the operation must
typically
be shut down to remove the accumulated solids at the bottom of the tank. This
obviously
requires time for the shut-down process, the emptying of the waste out of the
evaporator, and
the start up again of the combustion system. This can lead to a significant
down time, which
also means that well operations can be affected.
It is therefore desirable to provide a means to handle the accumulated solids
from
water evaporation systems such as but not limited to submerged combustion
applications that
allow the continuous operation of the evaporation process without the need to
shut down
same to remove the accumulated solids. The balance of cost, time and
operational efficiency
has created a need for new and improved treatment systems for wastewater. The
above
discussed limitations in the prior art is not exhaustive. Thus, there is a
need for an apparatus,
method and system to separate the components from wastewater utilized well
production that
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maximizes efficiency and is environmentally friendly. The current invention
provides an
inexpensive, time saving, more reliable apparatus, system and method where the
prior art
fails.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of
wastewater
treatment associated with well operations now present in the prior art, the
present invention
provides a new and improved wastewater separation apparatus, system and method
of use,
which may also be removably positioned to oil and gas wells. As such, the
general purpose
of the present invention, which will be described subsequently in greater
detail, is to provide
a new and improved wastewater treatment application which has all the
advantages of the
prior art devices and none of the disadvantages.
To attain this, the present invention essentially comprises a closed loop
system that
generally utilizes a pump in communication with a evaporating treating tank
discharge
wherein the suction end of the pump is connected to an opening on the bottom
of an
evaporator and or treating tank; a line then connects the discharge of the
pump to the inlet
opening of a separation tank; and a line then connects to the outlet opening
of the separation
tank back to an opening in the evaporator and or evaporator holding tank. As
the solids fall
to the bottom of the treating tank, they enter into the suction end of the
pump and are
discharged to the separation tank via a pipe or hose. The separation tank uses
the properties
of gravity, cooling and time to separate the suspended solids from the free
water. As the
solution cycles through the separation tank, the suspended solids fall to the
bottom of the
tank, while the free liquid floats across the top. The free water then exits
the separation tank
through an outlet opening and returns to the treating tank via a hose or pipe.
Over time, the
separation tank fills up with solids and is then emptied as desired while
leaving the evaporate
to remain operational.
The current invention may be utilized in fracking operations, well production
in
general, drilling operations, permanent placement at the well and so forth. It
is also
understood the current invention may be utilized in other applications where
it is desirable to
separate solids from liquids other than oil and gas applications.
There has thus been outlined, rather broadly, the more important features of
the
invention in order that the detailed description thereof that follows may be
better understood
and in order that the present contribution to the art may be better
appreciated. There are, of
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course, additional features of the invention that will be described
hereinafter and which will
form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in
detail, it
is to be understood that the invention is not limited in this application to
the details of
construction and to the arrangements of the components set forth in the
following description
or illustrated in the drawings. The invention is capable of other embodiments
and of being
practiced and carried out in various ways. Also, it is to be understood that
the phraseology
and terminology employed herein are for the purpose of description and should
not be
regarded as limiting. As such, those skilled in the art will appreciate that
the conception upon
which this disclosure is based may readily be utilized as a basis for the
designing of other
structures, methods and systems for carrying out the several purposes of the
present
invention. It is important, therefore, that the claims be regarded as
including such equivalent
constructions insofar as they do not depart from the spirit and scope of the
present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent
and
Trademark Office and the public generally, and especially the engineers and
practitioners in
the art who are not familiar with patent or legal terms or phraseology, to
determine quickly
from a cursory inspection the nature and essence of the technical disclosure
of the
application. The abstract is neither intended to define the invention of the
application, which
is measured by the claims, nor is it intended to be limiting as to the scope
of the invention in
anyway.
Therefore, it is an object of the present invention to provide a new and
improved
wastewater treatment application with a separator and method of using the
same, which may
be easily and efficiently utilized.
It is a further object of the present invention to provide a new and improved
wastewater treatment application with a separator and method, which is of a
durable and
reliable construction and may be utilized with multiple wells.
An even further object of the present invention is to provide a new and
improved
wastewater treatment application with a separator and method, which is
susceptible to a low
cost of manufacture with regard to both materials and labor, and which
accordingly is then
susceptible to low prices of sale to the consuming industry, thereby making
such tool
economically available to those in the field.
Still another object of the present invention is to provide a new and improved
wastewater treatment application with a separator and method, which provides
all of the
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advantages of the prior art, while simultaneously overcoming some of the
disadvantages
normally associated therewith.
Another object of the present invention is to provide a new and improved
wastewater
treatment application with 'a separator and method, which maximizes
evaporation of water
and concentrates solids for disposal, creates an opportunity for beneficial
use of reclaimed
solids and or reduces waste volume and weight through dewatering.
Yet another object of the present invention is to provide a new and improved
wastewater treatment application with a separator and method that may be
generally mobile,
may be moved from site to site with existing transportation equipment and
provides efficient
and effective loading, offloading and transportation in general.
An even further object of the present invention is to provide a new and
improved
wastewater treatment application with a separator and method, which improves
the
evaporation process in general, is environmentally friendly and provides the
opportunity to
reuse condensed water.
Still another object of the present invention is to provide a new and improved
wastewater treatment application with a separator and method, which reduces
risky, high-cost
handling; increases production through shut-down avoidance; and improves cost
management
predictability.
Yet still another object of the present invention is to provide a new and
improved
wastewater treatment application with a separator and method, which may be
utilized in
aspects of oil and gas operations as well as other applications where it is
desirable to remove
solids from wastewater or water in general.
Still another object of the present invention is to provide a new and improved
wastewater treatment application with a separator and method, which has a
small foot print as
well as ease of start-up.
A further object of the present invention is to provide a new and improved
wastewater treatment application with a separator and method that dewaters
solids optimally
thereby able to pass the paint filter test and qualifying waste solids for
landfill disposal,
prevents hardening and solidification of the solids to a level that would
prevent easy offload
at the landfill and provides a consistency of solids combined with separation
container design
making disposing of solids quick and efficient.
An even further object of the present invention is to provide a new and
improved
wastewater treatment application with a separator and method that generally
has one moving
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part associated with the separator thereby making downtime minimal, reducing
maintenance
and providing a safe operation.
These, together with other objects of the invention, along with the various
features of
novelty, which characterize the invention, are pointed out with particularity
in the claims
annexed to and forming a part of this disclosure. For a better understanding
of the invention,
its operating advantages and the specific objects attained by its uses,
reference should be had
to the accompanying drawings and descriptive matter in which there are
illustrated preferred
embodiments of the invention.
BRIEF DESCRIPTION OF THE PICTORIAL ILLUSTRATIONS,
GRAPHS, DRAWINGS AND APPENDICES
The invention will be better understood and objects other than those set forth
above
will become apparent when consideration is given to the following detailed
description
thereof. Such description makes reference to the annexed pictorial
illustrations, graphs,
drawings and appendices wherein:
Figure 1 is a general illustration of a preferred embodiment of the invention.
Figure 2 is general illustration of a preferred embodiment of the invention
but not
depicting an evaporator.
Figure 3 is a general perspective view illustration of a preferred embodiment
of the
invention but not depicting an evaporator.
Figure 4 is general side view illustration of a preferred embodiment of the
invention
but not depicting an evaporator.
Figure 5 is a general perspective view illustration with a partial cut away of
a
preferred embodiment of the invention but not depicting an evaporator.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the illustrations, drawings, and pictures and to Figure 1 in
particular,
reference character 10 generally designates a new and improved apparatus,
system and
method of using same constructed in accordance with the present invention.
Invention 10 is
generally used with a well utilized for the retrieval of hydrocarbons below
the surface. It is
understood that invention 10 may be utilized in numerous other applications
where it is
desirable to treat wastewater and the current invention should not be
considered limited to
just oil and gas applications. Furthermore, it is also to be understood that
the current
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invention is not limited to flow back water operations, well production,
drilling operations,
permanent placement and so forth. It is understood that numerous other
applications in the
oil and gas supply chain are contemplated where it is desirable to treat
wastewater by
concentrating and or separating solids from liquids. It is therefore
understood that the current
invention may be utilized with multiple applications.
Invention 10 contemplates providing solids management for a submerged
combustion
process through solids removal, solids storage, solids dewatering and
generally forming a
dewater cake to meet landfill requirements and or will pass a paint filter
test. Invention 10
contemplates a process that allows continuous or intermittent operation to
manage solids such
as but not limited to transfer via pressure pumping, separation via gravity,
separation via
retention, separation via filter media, separation via crystallization caused
by temperature
change and or transfer via gravity.
Therefore, invention 10 may generally comprise a wastewater source 20 such as
but
not limited to a holding tank, staging tank, inlet pipe and so forth, an
evaporator and or
treating tank system 30 for treating influent water and or wastewater 40, a
separation tank 50
in communication with evaporator 30. It is contemplated that evaporator 30 may
utilize
submerged combustion heating for evaporation although it is understood that
the current
invention is not limited to such. Other forms of wastewater treatment systems
known in the
art are contemplated to be used in association with the current invention as
well as other types
of evaporators.
Treating tank 30 may be referred to in the specification as evaporator,
evaporator
tank, evaporation tank, evaporator system and so forth. Separation tank 50 may
be referred
to in the specification as separator, separator tank, resting tank, separation
tank system and so
forth. Wastewater source 20 may also be referred to as holding tank, stock
tank, staging tank
and so forth.
As known in the prior art, submerged combustion heating is generally a method
whereby hot products of combustion are forced through a liquid or liquid-solid
mixture to
heat the liquid or liquid-solid mixture. An advantage of this heating system
is that the heat
exchange occurs directly between the hot gaseous products of combustion and
the liquid. In
a submerged combustion system and or evaporator, the hot combustion is
typically fuelled by
a combination of air and natural gas. Another benefit of such application is
the natural gas
needed to fuel the evaporation may come from the well operation thereby
eliminating the
need for transporting a fuel.
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In a desalination process, solids 35 such as but not limited to salts,
minerals and other
various matter are generally dissolved, broken down, burned and or suspended
for separating
from the wastewater 40. Solids 35 are further discussed below regarding
compositions types
and the term "solids 35" should not be considered to limit the invention as
such and is to be
considered to generally refer to solid matter in the wastewater 40.
In a thermal process, as the influent water and or wastewater 40 is heated,
the
dissolved solids 35 become concentrated and turn into suspended solids 35.
After the
dissolved solids 35 become suspended, the concentrated solids 35 fall to the
bottom of
treating tank 30 in which the heat treating occurs, while the free wastewater
moves towards
the top of treating tank 30 in the form of a vapor 60. The vapor 60 then exits
the treating tank
30 through an opening and or aperture 70, most commonly referred to as a stack
or an
exhaust. To continue the desalination process, the solids 35 eventually must
be removed
from the treating tank 30.
The output 80 from evaporator 30 that is not in the form of vapor 60 generally
comprises heavy hydrocarbons 90, precipitated solids 100 once dissolved, small
solids 110,
formation solids 120 and high total dissolved solid in water and or liquids
130 also referred to
as TDS water. Formation solids 120 may be dirt, rocks and other fines.
To move output 80 from evaporator 30 to separator 50, it is contemplated to
utilize a
pump 140. In a preferred embodiment, pump 140 may be located on the bottom of
coned
bottom treating tank 30, stand alone, be attached to separation tank 50,
combinations thereof
and so forth. It is also contemplated that more than one pump 140 may be
utilized.
Evaporator 30 may include an outlet and or aperture 150 such that suction end
of pump 140 is
connected to and or communicates with outlet 150. Invention 10 may include
conduit or line
160, which may connect to discharge port of pump 140 to an inlet, opening or
aperture 170 of
separation tank 50. Pump 140 may be but is not limited to a diaphragm
discharge pump
equipped with check valves with heavy balls, coated internals and flanged
connections.
Another conduit, line, pipe, aperture and or outlet 180 may move output 190
from
separation tank 50 back to evaporator 30 as discussed further below. It is
also understood
that another pump may be utilized but not depicted to move output 190 from
separator tank
50 back to evaporator 30 and it is also contemplated that output 190 from
separation tank 50
may go to holding tank 20 and combinations thereof
Separation tank 50 may be configured as a "roll-off' whereby the unit may be
rolled
on and or off a truck as known in the art. It is also understood that
separation tank 50 may be
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configured to be moved in other various known methods in art and the current
invention
should not be considered limited to the depictions in the illustrations.
Separation tank 50 may include an access manhole 200, a top 210, a bottom 220,
a
door and or first end 230, a second end 240, a length 250, an interior 260. It
is contemplated
that first end 230 may open and use hinge(s) and or hinge system 270 to open
door 230 for
accessing interior 260. It may further include a wheel(s) and or wheel system
280. Interior
260 may generally have a smooth surfaces
It is contemplated that separation tank 50 may further include a filter and or
filter
membrane 290 for allowing water to pass out of separation tank 50 while
retaining larger
particulates and solids in general. Filter 290 may be removable, attached to
door 230,
disposable, made from felt, felt like fabric, other known filter materials and
so forth.
Invention 10 contemplates inlet 170 of separation tank 50 may communicate,
connect,
attach and so forth to trough 300 such that as output 80 from evaporator 30
enters separation
tank 50 and is generally dispersed along the length 250 of interior 260.
Trough 300 may be
of numerous configurations such as but not limited to an open viaduct, closed
and or covered
viaduct with holes and or apertures along the length and so forth. Trough 300
may be
generally horizontally positioned; although it is contemplated, it may be
angled inside
separation tank 50 as discussed further below.
Invention 10 contemplates resting tank 50 on support structure, platform, and
or skid
310. Resting tank 50 may be constructed and or utilized without skid 310. In a
preferred
construction, resting tank 50 is set at an angle and or slope 320 such that
output 190 generally
utilizes gravity to move out to the line 180. Angle 320 may be about 5 degrees
although
greater and lesser angles are also contemplated. It is therefore contemplated
that skid 310
may have a top surface 330 that is at an angle to provide angle 320 to resting
tank 50.
Resting tank 50 may incorporate an angle 320 such that no skid 310 is
utilized. Resting tank
50 may include an angled interior surface by example.
It is contemplated that trough 300 is generally angled inside resting tank 50
to
reversely correspond with angle 320. This will allow trough 300 to remain
generally
horizontally positioned while resting tank 50 is set at angle 320. Skid 310
may further
include a drip pan 340 for catching liquids and or output 190 from outlet 180.
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IN OPERATION
Invention 10 contemplates that the addition of separation tank 50 increases
operational efficiency of evaporator 30 through dilution of the return of
output 190 and or
water 130 with lower wastewater 40 and converting suspended solids 35 in
return output 190
to dissolved form for more efficient evaporation processing. Further invention
10 allows
returning output 190 to be heating the wastewater 40 feeding from stock tank
20 to encourage
faster evaporation once the wastewater 40 enters the evaporation tank 30.
Separation tank 50 may dewater through crystallization initiated by
temperature
reduction achieved through tank design, combined with secondary nucleation via
interaction
with other non-salt solids, combined with gravity achieved through a
sloped/angled
separation tank design, combined with filter media placed at critical flow
points in the
separation tanks.
Therefore, invention 10 generally provides that solids 35 from wastewater 40
falls to
the bottom of evaporator and or evaporation tank 30 as a result of evaporation
such as but not
limited to the submerged combustion process and are then removed through the
use of a
pump 140 from same. The discharge pump 140 may be timed and volume set to
operate as
needed to manage the volume and consistency of the solids continuously such as
but not
limited to from 5 gallons per minute to 50 gallons per minute although other
amounts greater
and lesser are also contemplated.
Solids 35 are then pumped from the discharge pump 140 through outlet 150 pipe
or
hose able to handle material heated such as but not limited to 200
Fahrenheit into the high
temperature discharge pipe or hose to the separation tank 50 via inlet 170.
Separation tank 50
may use time, gravity, pressure, filter media, cooling and secondary
nucleation to separate
free water from the solids 35.
As solids 35 settle to the bottom 220 of separation tank 50, solids 35 may
form a cake
like substance 45 that generally stays moist enough that it may slide out of
separation tank 50
door 230 when door 230 is opened and separation tank 50 is tilted such that
gravity allows
substance 45 to slide out. It is understood that if substance 45 is too
hardened and or dry
substance 45 may not slide out as easily. Invention 10 contemplates substance
45 may meet
and or exceed landfill requirements as evidenced by the passing of the paint
filter test.
TDS water 130 and small solids 110 may then be returned from separation tank
50 to
the staging tank and or holding tank 20 via gravity through line and or pipe
180. Pipe 180
may also be referred to as an outlet for separator 50. It is contemplated a
pump may be
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utilized (not depicted). It is also contemplated that line 180 may go to
evaporator 30 and
combinations thereof. It is also contemplated to provide a lower total
dissolved solids water
130 rinse that may be initiated in the return line 180 to prevent scaling.
Staging tank 20 may be designed to isolate the returned suspended solids 35
and may
use air percolation 350 to agitate salt in the returned free water 130 to
defeat settling and
encourage return to circulation into the evaporation process. Returned
suspended solids 35
may be isolated within the staging tank 20 to be quickly returned to the
evaporation tank 30
via the inlet pump (not depicted) for further processing through the loop.
Holding tank 20 may include an outlet(s) 360 and an inlet 370. Evaporator 30
may
have inlet(s) 380.
As needed, when solids 35 and or substance 45 are at the desired level in the
separation tank 50, the separation tank 50 may be pulled with existing
transportation
equipment, transported to a landfill, tilted and emptied through gravity with
no secondary
clean out process needed. It is understood that clean out may not necessarily
require tilting
and that other forms of clean out may be utilized.
It is also understood that separation tank 50 may be used in combination with
another
separation tank 50 or others. One separation tank 50 may be hooked up to
evaporator 30
while the other is emptied and so forth. It is also contemplated that
evaporator 30 may
continuously run while separation tank 50 is removed and then replaced.
Separation tank 50
can process and separate solids continuously or intermittently as desired. It
is also
contemplated to run evaporator 30 and selectively utilize separator 50.
It is therefore contemplated that invention 10 may be wastewater treatment
system
comprising a holding tank for wastewater wherein said wastewater includes
solids therein
and wherein said holding tank has an inlet for receiving and an outlet for
passing said
wastewater; an evaporator for evaporating said wastewater, having an inlet for
receiving said
wastewater from said holding tank outlet, an outlet for passing said
wastewater that is
unevaporated and said solids from said wastewater; a separator for separating
and collecting
said solids from said wastewater, having an inlet for receiving from said
evaporator said
wastewater that is unevaporated and said solids from said wastewater; and an
outlet for
passing said wastewater to said holding tank inlet.
Invention 10 evaporator may be a submerged combustion evaporator, the
wastewater
from a producing oil and gas well, and the evaporator outlet is in
communication with a
pump for passing said wastewater and said solids to said separator inlet.
Still further
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invention 10 pump may be a diaphragm pump, the separator outlet further
includes a filter for
filtering said wastewater before passing said wastewater to said holding tank
inlet, and the
filter is made from fabric.
Invention 10 may include a skid adapted to support said separator at a slope
with said
separator outlet at the bottom of said slope, the separator is adapted to be
utilized as a roll-off
for transportation, and the skid further includes a drip pan.
Changes may be made in the combinations, operations, and arrangements of the
various parts and elements described herein without departing from the spirit
and scope of the
invention.
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